# OpenCPU

#### Andreas Blätte (andreas.blaette@uni-due.de)

#### 2019-12-17

## Objective

Sometimes, it is practically or legally not possible to move corpus data to a local machine. This vignette explains the usage of CWB corpora that are hosted on an OpenCPU server.

    library(polmineR)

## Remote Corpus

The GermaParl corpus is hosted on an OpenCPU server with the IP 52.24.44.232 (subject to change). To use the corpus, use the `corpus()`-method. The only difference is that you will need to supply the IP address using the argument `server`.

    gparl <- corpus("GERMAPARL", server = "52.24.44.232")

The `gparl` object is an object of class `remote_corpus`.

    is(gparl)

### Using polmineR core functionality

The polmineR at this stage exposes a limited set of its functionality for remote corpora. Simple investigations in the remote corpus are possible.

#### Get corpus size

    size(gparl)

#### Get structural annotation (metadata)

    s_attributes(gparl)

#### Subsetting

    gparl2006 <- subset(gparl, year == "2006")

The returned object has the class `remote_subcorpus`.

    is(gparl2006)

#### Simple count

    count(gparl, query = "Integration")

The `count()`-method works for `remote_subcorpus` objects, too.

    count(gparl2006, query = "Integration")

#### KWIC

    kwic(gparl, query = "Islam", left = 15, right = 15, meta = c("speaker", "party", "date"))

Works for the `remote_subcorpus`, too.

    kwic(gparl2006, query = "Islam", left = 15, right = 15, meta = c("speaker", "party", "date"))

## Next steps

Upcoming versions of polmineR will expose further functionality. This is a simple proof-of-concept!